Bilingual Cognitive Advantage: Where Do We Stand?

Linguistic experience and its effect on cognition

Like all other walks of life, academia is not immune to fashions. In the study of bilingualism, one such trend has been the study of “the bilingual cognitive advantage”, the theory that experience of using two languages – and selecting one, while inhibiting the other – affects brain structure and strengthens ‘executive control’ akin to other experiences, such as musical training, navigation, and even juggling. This strengthening has been linked to a variety of findings: the superiority of bilingual children and adults in performance on tasks requiring cognitive control, resistance of bilingual brains to cognitive decline, and the delayed onset of dementia (see here).

Touted in the popular media, these findings captured our hearts and minds and for good reason: for those of us who are bi- and multilingual, this is good news and the focus itself is a pleasant change from concerns about bilingual disadvantage that permeated many early debates on bilingualism. But has the pendulum swung too much in the other direction? Has bilingualism become a commodity we are trying to sell, instead of an experience we are trying to understand? And is there, in fact, a consensus that the knowledge of more than one language offers us something more than the joys of reading and conversing in two languages and a leg up in learning the third, among other things?

In the past few months, bilingualism researchers have engaged in a heated debate about the existence, scope, and sources of bilingual cognitive advantage on the pages of several scholarly journals. The upshot of the debate is that the desired consensus is nowhere in sight: the findings from different labs can be inconsistent and the blame for this is apportioned differently. Virginia Valian, a researcher at the City University of New York, blames the messy state of affairs on the unitary view of the executive function, which, in her opinion, needs to be better defined and investigated as an array of different processes. In turn, researchers from McGill University Shari Baum and Debra Titone see the key problem in the treatment of bilingualism as a unitary phenomenon. They argue that coarse comparisons of very heterogeneous groups ignore confounding variables, such as education, socioeconomic status, the effects of migration and, most importantly, the immense and rich variation in our linguistic experiences and interactional contexts.

Clearly, the experience of juggling two or more languages is not as uniform as that of juggling a few little balls and it raises intriguing questions. Is there a categorical difference between bilingual and monolingual experience or should we also see advantages in monolinguals who regularly shift between registers or dialects? Do languages matter: would Russian-Ukrainian bilingualism, for instance, confer the same advantages as bilingualism in English and French or German and Japanese? And what about the number of languages: are three better than two, and if so, why? What role is played by proficiency? Given that we see more advantages at higher levels of proficiency, is it possible that it is individuals with better executive control skills who become more proficient bilinguals? And what about language use: do we really have to use two or more languages on a daily basis to stall aging? If so, for how long? Is there a period after which the advantage becomes incontrovertible or is it always a case of “use it or lose it”? And what about the many differences in our interactional contexts and strategies? Do code-switchers have more of an advantage because they switch so frequently or less because they do not keep their languages “apart”? And what about translinguals like Nabokov who never fully suppress their other language and let it peek through their speech or writing in the “selected” language?

As the questions proliferate, we are witnessing an emerging consensus that a complex issue deserves a complex treatment, and I fully agree with François Grosjean who explained in an earlier post that the difference between bilinguals and monolinguals, when any are found, are specific to a particular task, and sometimes even a particular population, and can be quite subtle (see here). And as to the overall "bilingual cognitive advantage", it appears that the researchers are moving beyond this captivating label that promised a simple ‘yes’ or ‘no’ answer in the domain where there are no simple answers and towards more nuanced and sophisticated explorations of our linguistic experience and its effects on cognition; so stay tuned.

I take a Developmental Psychology Course in which we have covered this during our toddlerhood section of the class. Our professor did say that although in the beginning a bilingual child may find it dificult to aquire both languages at once later it shows that there isn't much of a delay compared to those who are just single language speakers. Personally, being bilingual, I did find it difficult when I was little learning English. My first language is spanish. In order for me to learn English I had to take ESOL classes when I was in my first couple of years of Elementary school. Now that I am older I can easily switch from using English and Spanish. In fact, learning a third language, that being French it made it easier on me to learn because I already knew spanish. I speak both languages at a very high level I believe and it's not hard to switch from using one language to another.

You relay concerns that education and socioeconomic status might be confounding variables. Are you able to say more about how these factors could (hypothetically) impact upon procedural language processing or upon control tasks (e.g. Simon tasks/Flanker) upon which some of the evidence for cognitive advantage is based? Is there another manner in which SES is thought to confound the cognitive advantage (working memory, etc.)?